Motorcycle exhaust pipe system



FIG. 1 is a front elevational view;

FIG. 2 is a bottom plan view;

FIG. 3 is a left side elevational view;

FIG. 4 is a right side elevational view;

FIG. 5 is a rear elevational view;

FIG. 6 is a top plan view; and,

FIG. 7 is a front elevational view of my motorcycle exhaust pipe system or a reduced scale.

The dotted lines showing a motorcycle in FIG. 7 are environmental only and form no part of the claimed design. 

The ornamental design for a motorcycle exhaust pipe system, substantially as shown and described. 